SpaceX CEO Elon Musk made a splash at the International Astronautical Conference in Mexico with his plans for an Interplanetary Transport System, along with a disturbingly inspirational ultimatum:

"There are really two fundamental paths," Musk said. "One path is we stay on Earth forever and there will be some eventual extinction event. ... The alternative is to become a space-faring civilization and a multiplanet species, which, I hope you would agree, that is the right way to go."

Unless we slip the surly bonds of Earth, humankind is doomed. The only alternative — the right thing to do — is to colonize Mars. Manifest destiny!